PIGEON FORGE, Tenn. —  Some charitable organizations in Tennessee are urging state lawmakers change the way they approve specialty license plates. The charities are worried they will collectively lose millions of dollars if the American Civil Liberties Union (search) wins its federal lawsuit against one of the tags.

The state has more than 100 specialty license plates that commemorate everything from the Sons of Confederate Veterans (search) to universities in other states.

But when the abortion debate came into the mix — with the Tennessee Legislature approving a "Choose Life" plate but rejecting a "Pro-Choice" plate — the ACLU sued to have it kept off license plates.

"What you had was the Tennessee General Assembly then approving one side of the message," said Hedy Weinberg of the ACLU of Tennessee.

But some fear the debate could jeopardize the entire program — not just license plates supporting political causes, but those raising money for charities, which support everything from childrens' hospitals to the environment.

"Specialty plates cost $35. We get 31 of the $35," said Jim Hart, friends of Great Smoky Mountains National Park (search). Hart said his organization earns $600,000 a year from the plates.  

Click here to watch a report by Fox News' Jonathan Serrie.